727 Kickdown ?

[RobP]

The more I work on my car, the more I realize I have SO much to learn!
Is there anyway to get the car to kickdown to 2nd from 3rd without going full throttle? I'd prefer to be able to kickdown to 2nd at anything over say 75% throttle. I'm currently running a Holley 670 and full throttle kickdown works just fine.

 

[oldbee]

Well adjusting the kick down linkage a little 'might' work. Early '70's valve bodies had that built in which is probably better way to do it.When ya get right to it just move to 2nd on the shifter(?)

 

[Lionized]

It should certainly be "part throttle" kickdown.
Is this a factory rod style?
Do you have a FSM?

 

[Fran Blacker]

Your throttle pressure control linkage (kick down) probably isn't adjusted right. Down load service manuals and parts books at:

http://www.mymopar.com/index.php?pid=31

 

[mentor70]

i cant remember the exact year that part throttle knockdown was introduced, but most of the latter Mopar trannys had them all the way into the early 90s.

you need this piece off the latter cars valve bodies to do it. and the valve body needs to be removed to add the valve to the main valve body.

 

[727]

You might be surprised to see how much a larger carb will change your throttle span and kickdown/throttle opening position. I didn't like the smaller carb (600cfm) on my 383. It seemed like it when I wanted to ease into the throttle, the tranny would kickdown. With a 750cfm I can roll on the throttle without a downshift, and make it kickdown when I want to really get on it. Basically got more throttle opening (fuel/air) with the tranny kickdown lever in the same position.

 

[RobP]

Here's my setup, not sure if that helps.

I'm editing this post as my picture of the throttle cable "play" was just because the carpet was hanging up the pedal assembly. The cable is the right length.
Thanks for everyone's input.

 

[Fran Blacker]

Don't think FSM will help you. Think the mount where throttle cable mounts doesn't give you enough pull to open throttle. I'm sure someone will chime in, seen similar problems. I deal with mostly stock stuff.

 

[RobP]

Upon further inspection, the throttle cable was loose at the pedal:

I loosened this bracket and pulled the cable towards the firewall and locked it back in place:

Cable is now snug but not too tight:

As to whether this will give me more throttle travel, it will have to wait until tomorrow when the weather clears up.

 

[Fran Blacker]

That's more betterer. Alert the grammar and the spelling police.

 

[oldbee]

RobP the reason I said to manual shift was after not driving mine for 20+ yrs I was never sure if I was in 2nd or 3rd(?) Noises are a lot louder compared to nowadays(LOL). But a manual shift ALWAYS let's you know where you are at! Boy these old things are noisy!

 

[Fran Blacker]

Upon further inspection, the throttle cable was loose at the pedal:
View attachment 416659

I loosened this bracket and pulled the cable towards the firewall and locked it back in place:

View attachment 416660

Cable is now snug but not too tight:

View attachment 416661

As to whether this will give me more throttle travel, it will have to wait until tomorrow when the weather clears up.

When I set mine up I jam the gas pedal to the floor and move throttle lever to make sure it's at full throttle. You can just look down the carb also.

 

[oldbee]

Fran it's more fun to check it out in the driver's seat, while moving!

 

[Fran Blacker]

Fran it's more fun to check it out in the driver's seat, while moving!

Of Course! You have to check your work.

 

[RobP]

I can now kickdown to 2nd at part throttle at any speed up to around 35, but over 35 it takes almost full throttle (85% i'd guess?). Better than before

I may end up bringing it over to the shop that installed the TF2 shift kit to fine tune it. Above my pay grade....

 

[oldbee]

W/o 'mentor70's' mod I don't think ur ever going to see 50% throttle kick down on ur trans.

 

[oldbee]

AND I think it takes a different valve body.

 

[Bruzilla]

You need to adjust the kickdown lever. The way I do it is to loosen the nut(s) that hold the adjustment slider or cable in place. Then, push the kickdown lever towards the rear of the car as far as it will go. Then move the throttle to where you want it to be when the kickdown is all the way back, and lock it all down.

Don't rely on photos of other cars as the correct location will vary based on the carb, linkage, lever, etc. Just use the location of the rod end when the rod is all the way back as your guide.